exstream

API · Create

exstream()

Adapt an existing source into one lazy, backpressure-aware pipeline model.

Sources

Accepted sources are existing Exstreams, promises, synchronous and asynchronous iterables, Web ReadableStreams, Node readable streams, or no source for a manually writable stream. Existing Exstreams are returned unchanged. Source adapters preserve their natural pressure model; see Create a source for complete examples.

Options

bufferLimit

Type non-negative integer or InfinityDefault Infinity

Maximum queued data/error records. The end marker does not count toward this limit.

overflow

Allowed 'error' | 'drop-oldest' | 'drop-newest'Default 'error'

Error throws BufferOverflowError. Drop policies require a finite limit and update dropped.

signal

Type AbortSignalDefault none

Aborts the stream with the signal reason; an already-aborted signal creates an already-aborted stream.

start

Allowed 'auto' | 'manual'Default 'auto'

Automatic mode activates from downstream demand. Manual mode keeps the root graph open for reliable fork registration until start().

Errors and runtimes

Invalid source types throw synchronously. Iterator/read failures enter the record-error protocol with source provenance. Node stream support is selected by the Node entry; browser builds use Web streams and portable codecs. Source adapters acquire iterators and platform readers on demand. Use defer() to postpone creation of the source object itself.

Signature

exstream<T, C extends object>(source: Exstream<T, C>, options?: StreamOptions | null): Exstream<T, C>
exstream<T>(source: PromiseLike<T>, options?: StreamOptions | null): Exstream<Awaited<T>>
exstream<T>(source: Iterable<T> | AsyncIterable<T>, options?: StreamOptions | null): Exstream<T>
exstream<T>(source: ReadableStream<T> | NodeReadableLike<T>, options?: StreamOptions | null): Exstream<T>
exstream<T = unknown>(source?: null, options?: StreamOptions | null): Exstream<T>

interface StreamOptions {
  bufferLimit?: number
  overflow?: 'error' | 'drop-oldest' | 'drop-newest'
  signal?: AbortSignal
  start?: 'auto' | 'manual'
}

defer(), fromEvent(), write(), stream state, Create a source